Chester Calma, SIGOS

Chester Calma is currently is the Manager for Technical Sales in the Americas at SIGOS. He is based in the San Francisco Bay Area and has worked on mobile operator’s VAS and signaling systems for the past 17 years. Within SIGOS, Chester provides customers with the best practices on how to test and monitor network quality including billing validation.

Prior to joining SIGOS, Chester worked at Mobileum while embedded at different mobile operators around the world.

He holds a Bachelor’s in Computer Science from De La Salle University in Manila, Philippines.

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